Utilization of Acetyl Salicylic Acidand Irradiation as Postharvest Treatments for Storage of Persimmon Fruits Cv."Costata"

Mature Persimmon fruits "Costata cv." were used to study the effect of Acetyl Salicylic Acid (ASA) at rates 0, 2, 3% and/or irradiation (IRD) with 0.0, 1.0, 2.0 KGy doses, using CO60 source at 2g /Sec as a trial for prolonging fruit marketing period and extending its shelf life with good quality, after cold storage treatment. Nine treatments including control were stored for 75 days at 0 ± 1oC with 80 + 2% relative humidity to measure weight loss, fruit firmness and decay percentages. Where, fruit quality parameters during shelf life were evaluated after 7 days of transference to room temperature (23 ± 2°C). Results showed a close relationship between high irradiation dose (2 KGy) and rate of detrimental effects by accelerating ripening process and softening during storage and shelf life to obtain less marketing fruits. Adding ASA at either 3 or 2% to fruits irradiated with2 KGy, slightly reduced the decline in fruit quality. Furthermore, non-treated cold stored fruits dominated 2 KGy treatment, in this respect.However, fruit constituent values were gradually progressed and 1 KGy dose recorded the highest storability effect in keeping fruits firm with less deterioration response as combined with 2% ASA, compared with sole ones.Moreover, improving effect in fruit components i.e., acidity, VC, SSC, sugar, T. flavonoids, β-Carotene and reduction in tannin contents were retained with 1 KGy treatment as combined with 2% ASA followed in descending order by 3% ASA. In general, irradiation of persimmon fruits at dose (2 KGy) was not suitablefor preserving stored fruits. Also, sole radiation treatment at 1 KGy was less effective than sole treatment of ASA at either 2 or 3% rates, in this respect. Therefore, irradiation with 1 KGy combined with ASA treatment at 2% can be recommended for improving storability of persimmon"Costata cv." fruits with the maintenance of good marketable and preferable nutritional parameters up to extended shelf life.

Influence of Multifunctional Monomers on Gamma Irradiated Polylactic Acid

The aim of this work was to compare and discuss the influence of multifunctional monomers as crosslinking agent (Triallyl Isocyanurate; TAIC) and chain extender (Joncryl ADR4368) on the gamma irradiated Polylactic acid (PLA). The modified PLA samples with varying amount of TAIC and Joncryl were characterized by observing the molecular characteristics and mechanical properties. The results showed that irradiated PLA had lower average molar mass and mechanical properties compared to non-irradiated PLA due to irradiation induced chain scission. Gel content was observed and increased with increasing irradiation dose for the TAIC modified sample, indicating that the further crosslink of irradiated PLA was occurring. Crosslinking and chain extension were responsible for the improved modulus and tensile strength of irradiated PLA, however the decrease in tensile strength at high irradiation dose was observed for crosslinked PLA.

Outcomes of chemoradiotherapy with a high irradiation dose using a 3D radiation treatment planning system for esophageal cancer.

89 Background: The standard irradiation dose of chemoradiotherapy (CRT) for esophageal cancer is 50.4 Gy, however, the trials in which this standard dose was originated were based on 2D radiation treatment planning. In this study we assessed the survival and toxicities of CRT with a dose of 60-66 Gy using a 3D radiation treatment planning system (3DRTPS) for esophageal cancer. Methods: One hundred and two eligible patients with esophageal cancer treated by definitive CRT between 2000 and 2006 were assessed. Median age was 67 years old. There were stage I in 22 patients, stage II-III (without T4) in 27 and T4/M1Lymph legions in 53. There were 100 patients with squamous cell carcinoma histology and 2 with small cell carcinoma. Main tumor sites were cervical/upper/middle/lower thoracic in 15/19/43/25 patients. Treatment planning of irradiation was performed using a CT based 3DRTPS. Total irradiation dose of our protocol was 60-66 Gy. Accomplishment rate of planned irradiation was 93%. All patients received chemotherapy concurrently with radiotherapy. Fluorouracil based chemotherapy was performed in 96 patients (94%). Results: The data was updated in August 2010. The median follow-up was 67 months. Cause-specific survival rates at 5 years for stage I, II-III (without T4) and T4/M1lymph were 100%, 49% and 17%, respectively and overall survival rates were 66%, 35% and 13%, respectively. Complete response (CR) rates were 100%, 79% and 35%, respectively and failure rates of CR cases were 5%, 43% and 42%, respectively. Late adverse effects (≥ grade 3) were observed in 11 patients (10%); pneumonitis in 4 (4%), pleural effusion in 4 (4%) and pericardial effusion in 5 (5%). Treatment related deaths were observed in 2 cases (pneumonitis developed during treatment in 1 and debility due to treatment in 1). Conclusions: Toxicities of CRT with a high irradiation dose using 3DRTPS for esophageal cancer were acceptable and survival was promising. Dose intensification study of 50.4 Gy versus ≥ 60 Gy in CRT using a 3D-conformal radiation therapy technique for esophageal cancer should be considered. No significant financial relationships to disclose.

Impermeable Graphite: A New Development for Embedding Radioactive Waste

The natural occurrence of graphite proves its geological stability over long time periods and therefore it could be considered as a matrix for embedding radioactive waste. However its porous structure affects the possible use of graphite as long term stable waste matrix for final disposal. Aqueous phases can penetrate the pore system and radionuclides adsorbed on the surface can be leached. Furthermore slow corrosion in aquatic phases can be induced by high irradiation dose rates in the range of 10−5 to 10−7 gm−2d−1. Therefore radiation induced corrosion process cannot be neglected in geological time scales. These problems can be solved with a graphite material with a closed pore system. A graphite composite material with an inorganic binder has been developed with a density > 99.7% of theoretical density and a negligible porosity. An initial calculation predicts that the life time of the graphite will be at least 2 orders of magnitude higher than porous graphite. This material represents a long term stable leaching resistant matrix applicable for the embedding of irradiated graphite (i-graphite). Natural graphite can be added to improve the compaction behavior and mechanical properties. Additional applications could be the embedding of other radioactive wastes in this matrix.

Mechanism of Ion-Induced Solid-Phase Crystallization and Amorphization

ABSTRACTA mechanism is proposed to explain ion-induced solid-phase epitaxial growth (SPEG). It is argued that radiation-enhanced diffusion in amorphous solid is the cause of ion-induced SPEG at relatively low temperatures. The atoms in the amorphous solid near the crystalline/amorphous interface adjust their positions to lattice sites due to a free energy decrease associated with the transformation from amorphous to crystalline solid. An expression for the velocity of ion-induced SPEG is derived. At low temperatures and high irradiation dose rates, a large number of atoms in the lattice gets displaced and the free energy of the crystalline solid can increase to such a value that the crystalline/amorphous interface may remain stationary. It is shown that the dose rate at which the interface remains stationary increases with the temperature, following an Arrhenius dependence.